New type of autocollimator based on the normal tracing method and Risley prisms.
Applied Optics
|November 22, 2021
Summary
This study introduces a novel autocollimator using Risley prisms for accurate large-angle measurements. The system minimizes errors by employing a near-normal tracing method, enhancing precision in angular measurements.
Area of Science:
- Optical Engineering
- Metrology
Background:
- Traditional autocollimators face limitations in large angle measurement accuracy.
- Aberrations and processing defects can introduce significant errors in angular measurements.
Purpose of the Study:
- To propose a new autocollimator design for high-accuracy angular measurement over a large angle range.
- To reduce angle measurement errors caused by aberrations and working distance.
Main Methods:
- A novel autocollimator system integrating a traditional autocollimator with Risley prisms.
- Employing a normal tracing method by deflecting the beam close to the normal direction of the reflecting mirror.
- Calculating the mirror's tilt angle using autocollimator and Risley prism rotation angles.
Main Results:
- The near-normal tracing method minimizes angle errors from aberrations and optical defects.
- Theoretical analysis indicates angle error is independent of working distance.
- ZEMAX non-sequential simulations confirm significant reduction in aberration-induced angle errors.
Conclusions:
- The proposed autocollimator with Risley prisms offers a significant improvement in high-accuracy angular measurement.
- The normal tracing method effectively mitigates common error sources, enhancing measurement reliability.
- This system is suitable for applications requiring precise angular measurements across large ranges.
